A serious workout, especially in powerlifting gear, can and does often take over 2 hours. An accessory day is around an hour. I think the whole "you won't make gains if you take longer than xyz.." bit is extremely over rated. You don't want to be in the gym all day, and you don't want to drag your feet with your exercises, but saying you are wasting your time going over 45 min or an hour is just plain wrong too. I think originally this was aimed at the guys who are supersetting and hitting 15,000 different exercises in one day, and people just ran with it.